Magical Metal

Yesterday mentioned the gold and silver cramp rings used in the Middle Ages in England to avoid cramps and epilepsy. (The sample here—alas!—is a later iron version.) Gold and silver were precious not only for their rarity and beauty; it was the reason for their beauty that made them magical.

Gold and silver do not oxidize like iron and copper. This "metallic immortality" surely helped to enhance the idea that they were special in a magical way. In fact, gold was considered medicine by many early authorities.

An 11th century lecturer at Salerno, Constantinus Africanus, claimed:

Gold is more temperate than the other metals. It has the property of relieving a defective stomach and comforts the fearful and those who suffer from a heart complaint. Galen confirms that it is effective against melancholy and baldness.

 Obviously gold needed to be ingested for it to work. To do so required very small pieces, and the Arab physician Abulcasis explained the method for preparing gold for consumption:

Take a piece of good and pure gold; and have a plate with pure sweet water in front of you; and have a rough clean cloth of flax, one end of which you keep in your hand. The other end should stay soaking in water on the bottom of the plate. Then rub gold with the cloth, always moistening the cloth with water, and fine filings descend to the bottom of the container. Do so as long as much of that gold as you want to have been shaved. Then leave for an hour; and mix water speedily and wash three times and dry up and preserve it.

Gold-based preparations were called aurum potabile ("drinkable gold"), written about by Michael Scot, Roger Bacon and others. Making it drinkable was no small trick, but it could be made into a liquid by combining hydrochloric acid and nitric acid. This mixture was one of the only ways to dissolve gold, and inspired alchemists to believe that an actual, pure aurum potabile was possible. Paracelsus (1493 - 1541), who was adamant that one could improve upon Nature, and his contemporary Johan Isaäc Hollandus were certain that pure liquid gold could be achieved and would have unbelievable curative properties.

The consumption of gold over time, however, far from enhancing health produced "auric fever": fever, profuse sweating, excess urination, gastrointestinal problems, and kidney damage. Evidence of death by gold has been found.

In 2013, The Geological Society published a collection of essays called A History of Geology and Medicine. One article, "Pharmaceutical use of gold from antiquity to the seventeenth century," points out that there is at least one modern medicine that includes gold: Myocrisin, an injectable used for rheumatoid arthritis.

Back to the subject of liquid gold: who figured out that hydrochloric and nitric could dissolve gold? That was a 9th century writer who produced the oldest known classification system of chemical substances. His name was Jabir ibn Hayyan, and you'll learn more about him next time.

John of Garland

John of Garland (c.1180 - c.[at least] 1252) was an English grammarian and poet. (He wrote a poem about a recording demon.) Despite his English origin, he spent most of his life in France, first in Paris in 1202 to study, then at the University of Toulouse.

He left Toulouse around 1232 when the Cathars re-asserted themselves and university professors stopped being paid. He fled to the University of Paris, where Roger Bacon heard him lecture. It was this time in Paris that gave him his surname: he explains it is from the Rue Garlande in the neighborhood of the University.

There are over two dozen of his writings known (there are a few titles we know of, but have no extant copies). One was his Dictionarius (shown here), which was not a dictionary as we know it, but a textbook that attempted to teach Latin to French students at the University of Paris. Some credit Garland for the origin of the modern word "dictionary."

Besides works of instruction, he wrote poetry such as the Epithalamium beatae Mariae Virginis (“Bridal Song of the Blessed Virgin Mary”) and his account of the crusade against the Cathars, De triumphis ecclesiae (“On the Triumphs of the Church”). His hostility toward heresy was extended to Jews. To quote an author who wrote about this topic:

Although he never denied the possibility that conversion to Christianity could redeem the Jews, he thought it unlikely they would come over to the Catholic faith or remain steadfast in the religion. His invective was extreme by the standards of the time but was influential in that it appeared in many of his pedagogical works for adolescents and young men at the universities. [Journal of Medieval History, Vol.48, Issue 4]

Despite his time in France, his numerous writings were very popular in England, and were printed and re-printed in the 14th and 15th centuries.

Curiously, there was a second John of Garland who lived and wrote about the same time; this one was a music theorist, and will be our next topic. 

De Gradibus

De Gradibus (Latin: Concerning degrees) was written by the Father of Arab Philosophy, Al-Kindi (801-873CE). In it, he applies mathematics to medicine, demonstrating a method he invented to determine the proper strength of a drug for a patient. Also, he discusses the degrees of the phases of the moon and how they help a physician to determine the most crucial days of a patient's illness.

When it was translated into Latin, the complex mathematical reasoning made it difficult for Western Europeans to grasp. Roger Bacon appreciated his approach, and endorsed it thusly:

The degree can only be determined by the method taught by Al-Kindi’s De gradibus, one extremely difficult and almost entirely unknown among Latin physicians of these days, as everyone is aware. Whoever wants to become perfect in this philosopher’s art must know the fundamentals of mathematics, because the species of greater and lesser inequality, the species of ratios, and the very difficult rules of fractions are all used by this author.

Plinio Prioreschi, a 20th century expert on the history of medicine, credits Al-Kindi with the earliest attempt to quantify medicine.

Al-Kindi was heavily influenced by noted Greek physician Galen (129-216CE). The stereotype of a Muslim rejecting any non-Muslim source of knowledge is tossed out by Al-Kindi's approach to knowledge. He wrote:

We must not hesitate to recognize the truth and to accept it no matter what is its origin, no matter if it comes to us from the ancients or from foreign people. My purpose is first to write down all that the ancients have left us on a given topic and then, using the Arabic tongue and taking into account the customs of our time and our capacities, to complete what they have not fully expressed.

How did Arabic works come to be available to European scholars. Was it haphazard, or was there a deliberate move to share knowledge. Tomorrow we will learn about Gerard of Cremona, and for a double treat, we will also talk about Gerard of Cremona. (Not a typo.)

Roger Bacon's "Opus Majus"

Roger Bacon was born about 1219 into a wealthy family in England. He attended classes at Oxford University, where he learned a love of science from masters such as Robert Grosseteste and Adam Marsh. About 1240 he joined the Franciscans, which might have stifled his interests. There was a prohibition on the order against publishing without special permission from the superiors. This was in place because of a work published previously that was considered heretical.

Bacon looked for support and patronage from the papal legate to England, telling him that educational reform was needed. This was one Gui Foucois, although in England he was known as Cardinal Guy de Foulques. The cardinal was not interested in providing financial aid, but was interested in his work and ideas. Unfortunately, without money, Bacon could not afford the writing materials and scientific equipment to produce what he wanted to send.

Then, in 1265, the situation changed. Guy de Foulques was elected Pope Clement IV. Another request to the new pope returned the same result: Clement wanted the information, but would not send money. Bacon could only assemble a shorter work than he wanted to. The result was the Opus Majus or Opus Maius (Latin: "Greater Work"). Its seven sections (which included some of his earlier writings along with new materials) are:

•The Four General Causes of Human Ignorance (believing in an unreliable source,  sticking to custom, ignorance shared by others, pretending to knowledge)
•The Affinity of Philosophy with Theology (concludes that Holy Scripture is the foundation of all sciences)
•On the Usefulness of Grammar (a study of Latin, Greek, Hebrew, Arabic)
•The Usefulness of Mathematics in Physics (in this section he proposes changes to fix the Julian calendar)
•On the Science of Perspective (the anatomy of the eye and brain; light, vision, reflection and refraction, etc.)
•On Experimental Knowledge (a review of alchemy, gunpowder, and hypothesizes microscopes, telescopes, eyeglasses, machines that fly, and ships driven be steam)
•A Philosophy of Morality (philosophy and ethics)

It was sent to Clement in late 1267 or early 1268; however, Clement died in 1268. We do not know if he even had opportunity to read what he had requested.

"The Science of Perspective" was about optics. In that section, he discussed the anatomy of the eye, and how light is affected by distance, reflection and refraction. He also goes into mirrors and lenses. Most of this knowledge of optics came from Alhazen's Book of Optics, previously discussed here, and Robert Grosseteste's work on optics based on Al-Kindi, of whom I have never written before; I think there's my next topic.

For more on Bacon, use the search feature in the blog.

Asking Questions

Image from Adelard's translation
of Euclid's Elements of Geometry

Being inquisitive is the first step to learning.* In the early Middle Ages, the presence of many classical authorities circulating in Latin, such as Aristotle and Plato, eliminated the need for inquiry in the opinions of many.

The 12th century saw an influx of more works, many of them Greek writings (preserved by Arabs) or Arab writings. The widening of philosophical and scientific horizons by this wave of knowledge caused many scholars to re-think what had been established.

Adelard of Bath (c.1080-c.1152) was an English philosopher who was in a position to translate into Latin for the first time many of the Greek and Arabic works becoming available to the West. After studying at Tours and teaching at Laon in France, he traveled for seven years through Italy, Sicily, Syria and Palestine. He translated Al-Kwarizmi's astronomical tables and Euclid's Elements of Geometry from Arabic, wrote works on the abacus and on his love of philosophy, and a book called Questiones Naturales (Natural Questions) in which he tackled, in dialogue form, 76 questions about the world. One of his themes is the choice of using reason rather than merely accepting authority.

For what should we call authority but a halter? Indeed, just as brute animals are led about by a halter wherever you please, and are not told where or why, but see the rope by which they are held and follow it alone, thus the authority of writers leads many of you, caught and bound by animal-like credulity, into danger. Whence some men, usurping the name of authority for themselves, have employed great license in writing, to such an extent that they do not hesitate to present the false as true to such animal-like men. [...] For they do not understand that reason has been given to each person so that he might discern the true from the false. [Questiones Naturales, VI]

To be clear: Adelard's science is not ideal: his periodic table of elements contains only four substances, which are mixed in various proportions to create all materials. Some animals see better by day or night because of either white or dark humor in their eyes. We see because an extremely light substance (Plato's "fiery force") is created in the brain, gets out of the brain through the two eyes, swiftly reaches an object and learns and retains its shape, then returns to the brain through our eyes so that we "see" what is in front of us. A mirror, whose surface is smooth, bounces back the fiery force, which on returning to us picks up our image on its way and allows us to see our reflection.

Still, his works were copied and distributed, and influenced much of what was to come. His assertion of reason over blind acceptance of classical authorities was an important milestone in scientific thought. Many of his ideas are seen again in the writings of Robert Grosseteste, Roger Bacon, and Hugh of St. Victor. Once the printing press was perfected, Adelard's translation of Euclid became a standard text for a hundred years.


*One of the followers of this blog is part of a group trying to promote inquiry-based learning in young people. Visit Prove Your World to learn more.

Parochial School

One of the decrees that came out of the Fourth Lateran Council of Pope Innocent III was that "every cathedral or other church of sufficient means" was to have a master or masters who could teach Latin and theology. These masters were to be paid from the church funds, and if the particular church could not support them, then money should come from elsewhere in the diocese to support the masters. The interest of the Roman Catholic Church in providing education has a long history.

This did not start in 1215, actually: the Third Lateran Council of 1179 (called by Pope Alexander III) had already declared that it was the duty of the Church to provide free education "in order that the poor, who cannot be assisted by their parents' means, may not be deprived of the opportunity of reading and proficiency."

One wonders how carefully churches complied with this. Because the school was integral to the church it was attached to, records are not as abundant as they might be if the school were a separate legal entity with its own building, property taxes, et cetera. We have to look for more anecdotal and incidental evidence.

Among Roger Bacon's unedited works is a reference about schools existing "in every city, castle and burg." John of Salisbury (c.1120-1180), English author and bishop, mentions going with other boys as a child to be taught by the parish priest. (Note that this is long before the Lateran Council decrees; it seems they may have simply affirmed and extended a long-held practice.)

Schools for young boys stayed attached to churches for a long time. A late-medieval anecdote of Southwell Minster in Nottinghamshire (pictured here; believed to be the alma mater of Thomas Cranmer, Archbishop of Canterbury under Henry VIII) tells that a visiting clerk (priest) complained that the noise of the boys being schooled was so great that it disturbed the services taking place. And Shakespeare's Twelfth Night acknowledges these schools with the line "Like a pedant that/Keeps a school i' the Church." It would be a long time before schools for the young were deemed to need their own buildings.

Jacob Anatoli

Daily Medieval has frequently mentioned the importance of Arabic texts in the transmission of knowledge to Western Europe. Arabic, however, was not a commonly known language, and Arabs did not have a strong presence in Western Europe. Arabic culture often brushed up against Latin culture in the southern Mediterranean, as mentioned Salerno, or when a scholar such as Michael Scot made it a point to learn Arabic. Scot probably had help in the form of Jacob Anatoli.

Jacob ben Abba Mari ben Simson Anatoli (c.1194-1256) grew up in southern France, and gained such a reputation for scholarship that he was invited to Naples by Frederick II, who gathered several other academics to his court, such as Scot and Fibonacci. Anatoli became known for his translations of Arabic texts into Hebrew, and he very likely aided Michael Scot in his Arabic translations. Roger Bacon explains that Scot was aided by a Jew named Andreas, and some scholars believe "Andreas" to be a misunderstanding of "Anatoli."

Of his non-translations, the greatest work is the Malmad ha-Talmidim (the title is a pun, being interpreted either "Teacher of the Students" or "Goad to the Students"). The Malmad shows a wide range of knowledge, incorporating the Old Testament and Jewish commentators, but also the New Testament, Aristotle, Plato, and Averroes. His egalitarian approach to Christian and Muslim matters was refreshing, but Judaism still had special status; he wrote "the Greeks had chosen wisdom as their pursuit; the Romans, power; and the Jews, religiousness." He tells us that a non-Jew who seeks religious Truth should be respected by Judaism and not mocked.

Anatoli extended this intellectual courtesy to Frederick II, incorporating remarks by the emperor in his works. He also mentions a Christian whom Anatoli considers a second master (after Anatoli's own mentor, Samuel ibn Tibbon); this "master" has been equated to Michael Scot.

As for his Arabic translations, Anatoli's crucial contribution was exposing the West to the work of Averroes, one of two Arab scholars (the other was the medical expert Avicenna) whose work is considered fundamental to the Middle Ages.We'll look at Averroes tomorrow.

Battle of the Numbers

Among the accomplishments of Hermann of Reichenau, he also provides us with the set of rules for one of Europe's oldest board games, developed by a monk to teach Boethian number theory, called Rithmomachy or Arithmomachia, "Battle of the Numbers."

The pieces on the rectangular 8x16 board, their "ranks" and their allowed moves are determined by mathematical rules based on their geometry (Circles, Squares, Triangles, Pyramids) and the numbers marked on their surfaces. I could not possibly explain the rules in a short post—nor should I be able to, since the intent was to design a game that truly requires a grasp of mathematical functions and the skill to apply them quickly. Feel free to educate yourselves on the rules here and here.

Laser-etched pieces. [link]

It was more than just a game of strategy like chess (to which it has some resemblance). According to a 2001 book, Rithmomachy

combined the pleasures of gaming with mathematical study and moral education. Intellectuals of the medieval and Renaissance periods who played this game were not only seeking to master the principles of Boethian mathematics but were striving to improve their own understanding of the secrets of the cosmos. [The Philosopher's Game, Anne Moyer]

The game became popular as a teaching aid in monasteries in France and Germany, and even reached England where Roger Bacon recommended it to students at Oxford. Over the centuries it spread as an intellectual pastime, and by the Renaissance it had spread enough that instructions were being printed in French, German, Italian and Latin. Sadly (mercifully?), the game fell out of popularity and the public's consciousness after the 1600s until modern historians re-discovered it.

Chasing Rainbows

The formation of a rainbow is a complex matter, inspiring both wonder and curiosity. How they come about took a great deal of time, speculation, and ultimately experimentation.

Aristotle was sure that water droplets were involved, and he knew there was a relationship between rainbow, sun and observer. In his model, however, each water droplet in the air is a tiny mirror that reflects toward the observer a piece of color.

Since each of the mirrors is so small as to be invisible and what we see is the continuous magnitude made up of them all, the reflection necessarily gives us a continuous magnitude made up of one color; each of the mirrors contributing the same color to the whole. We may deduce that since these conditions are realizable there will be an appearance due to reflection whenever the sun and the cloud are related in the way described and we are between them. ... So it is clear that the rainbow is a reflection of sight to the sun. [Meteorologica, Book III, Part 4]

Among his other theories, Robert Grosseteste (c.1175-1235) rejected Aristotle's view that the rainbow was created by reflection; instead, he believed that light passing through clouds, rather than bouncing off them, produced the spectrum. Since every schoolchild knows that refraction breaks white light up into the spectrum, this seems to us like Grosseteste knew what he was talking about.

Then came Roger Bacon a generation later. Some believe he studied under Grosseteste. What is certain is that Bacon knew of Grosseteste's works, because he sometimes quotes them verbatim in his own writing. When it comes to the rainbow, however, Bacon does something that seems baffling on the surface. He rejects the refraction theory and returns to Aristotle's reflection theory. Modern historians shake their heads over this apparent retrograde thinking.

Christ on a rainbow, the Macclesfield Psalter

Bacon had his reasons, however, which make more sense once you know the details of Grossesteste's theory. Grosseteste required three separate refractions to take place, using the borders of the clouds in a complicated lensing effect. Bacon pointed out that a rainbow could appear in a simple spray of water, as in a fountain, and the clouds and interfaces needed for the complex refractions described by Grosseteste were clearly not involved. Bacon also pointed out that the view of the rainbow changed as the observer moved, which meant the rainbow was being reflected toward the observer while keeping its proportions and color. It did not stay "painted on the clouds" as if it were just projected there by light refracted through a cloud lens. (At this point, it is obvious that they did not yet understand "seeing" as light reflecting off objects and into the eye.)

Bacon didn't have all the answers, of course. He struggled to explain the curve in the rainbow, and the fact that it was not a solid half-sphere: why wasn't there color in the center? And he ignored refraction completely when discussing the rainbow, even though he used refraction to explain the occasional halo around the moon.

Did Bacon hold back scientific progress? Hard to say. Grosseteste's theory was valuable in that refraction is crucial in the formation of a rainbow, but he made several assumptions that could not be supported. He ignored the part played in the process by water droplets, even though Aristotle and—more recent to Grosseteste, Albertus Magnus (c.1200-1280)—had insisted on the part they played. Grosseteste thought the entire cloud was the refracting lens. Rainbows were still not properly understood, but the efforts made to comprehend something that could not be touched and experimented on were impressive.*

...and what of the accurate explanation of the rainbow?  A few years after Bacon's death, a disciple of Albertus Magnus would work it out. But that's for another day.

*More on Grosseteste, Bacon and their theories can be found in an article by David C. Lindberg in Isis, Vol.57, #2 (1966).

Fireworks

In honor of Independence Day in the USA...

Everyone knows that to discuss the history of fireworks means talking about China and Marco Polo (1254-1324), but the real history of fireworks in the European Middle Ages may start with Roger Bacon (1214-1294).

Bacon was a Franciscan Friar who spent time at Oxford and may have studied under Robert Grossteste. He has been called the first user of the scientific method, but more careful study of his works suggests that his conclusions and theories were the result of "thought experiments" like many other scholars, instead of actual scientific experimentation. Although Oxford's fairly careful and complete records of degrees given do not show that Bacon ever earned a doctorate, he was nicknamed Doctor Mirabilis (wonderful doctor) for his ideas.

Many volumes have been filled about Bacon, his ideas and discoveries, but today we are interested in gunpowder. At the request of Pope Clement IV, Bacon wrote his seven-part Opus Maius (Greater Work) which discussed (among other things) his thoughts on philosophy, theology, and certain scientific experiments. We know that a contemporary and fellow Franciscan, William Rubruck (c.1220-c.1293), visited the Mongols and witnessed the use of gunpowder in the form of firecrackers. Perhaps Rubruck brought some back. The relevant passage in the Opus Maius is:

We have an example of these things (that act on the senses) in that children's toy which is made in many [diverse] parts of the world; i.e. a device no bigger than one's thumb. From the violence of that salt called saltpetre [together with sulphur and willow charcoal, combined into a powder] so horrible a sound is made by the bursting of a thing so small, no more than a bit of parchment [containing it], that we find [the ear assaulted by a noise] exceeding the roar of strong thunder, and a flash brighter than the most brilliant lightning.

The "no more than a bit of parchment containing it" reminds me of these. He speaks of this again in his Opus Tertium (the Third Work; and yes, there had been an intermediate Opus Minus, the Lesser Work):

Then wonders can be done by explosive substances. There is one used for amusement in various parts of the world made of powder of saltpeter and sulphur and charcoal of hazelwood. For when a roll of parchment about the size of a finger is filled with this powder, it produces a startling noise and flash. If a large instrument were used, the noise and flash would be unbearable; if the instrument were made from solid material, the violence would be much greater.

These are the earliest references in the English-speaking world to gunpowder and fireworks. Whether Bacon ever made his own gunpowder is unknown, however. Some articles will tell you that he could, and encrypted the knowledge in order to prevent its misuse. Claims that Bacon hid the formula for gunpowder in his works cannot be substantiated, however. He seems to know what goes into the formula, but not necessarily in what proportion.  The secret numbers that some modern manuscript detectives claim to have found in his writings produce the wrong ratio for gunpowder to do more than smoke.

Enjoy your day.